American and Chinese scientists are flabbergasted after discovering a giant 298-million-year-old forest buried intact under a coal mine near Wuda, in Inner Mongolia, China.

They are calling it the Pompeii of the Permian period because, like the ancient Roman city, it was covered and preserved by volcanic ash.

Like Pompeii, this swamp forest is so perfectly maintained that scientists know where every plant originally was. This has allowed them to map it and to create the images above. This extraordinary finding "is like Pompeii", according to University of Pennsylvania paleobotanist Hermann Pfefferkorn, who characterized it as "a time capsule."

It's marvelously preserved. We can stand there and find a branch with the leaves attached, and then we find the next branch and the next branch and the next branch. And then we find the stump from the same tree. That's really exciting.

They are in fact finding entire trees and plants exactly as they were at the time of the volcanic eruption, just like archeologists in Pompeii found humans, animals and buildings at the base of Mount Vesuvius, near Naples, in the Italian region of Campania. Except Pompeei was buried in AD 79 and this forest was covered in ash 298 million years ago, during the Permian period.

The researchers discovered the 10,763-square-foot (1000-square-meter) area hidden under a coal mine using heavy industrial machinery. They believe that this frozen-in-time fossilized forest was covered under gigantic amounts of ash that fell from the sky for days.

So far, they have identified six groups of trees, some of them 80 feet tall. Some of them are Sigillaria and Cordaites, but they also found large groups of a type called Noeggerathiales, which are now completely extinct.

During the Permian, which extends from 299 to 251 million years ago, there weren't conifers or flowers. Plants reproduced like ferns, using spores, and the modern continents were still joined in a single mass of land called Pangaea. This geologic period happened at the end of the Paleozoic era, after the Carboniferous.

During this time there were also animals. This is when the first groups of mammals, turtles, lepidosaurs and archosaurs started to roam the Earth. Scientist believe that the Permian—and with it the entire Paleozoic era—ended with the largest mass extinction ever, which obliterated 90 percent of the marine and 70 percent of the terrestrial species.

After this event, the Mesozoic era started with the Triassic period. That's when the first true mammals evolved, the pterosaurs flew for the first time and the archosaurs' rose to dominate Earth.

Pfefferkorn worked on the project with Jun Wang of the Chinese Academy of Sciences, Yi Zhang of Shenyang Normal University and Zhuo Feng of Yunnan University. The results of their findings have been published in the journal Proceedings of the National Academy of Sciences. [University of Pennsylvania]